About one in 8 women (12%) will develop breast cancer in her lifetime and it is also causing the most cancer deaths in women aged 30 to 49. An impressive statistic that clearly demonstrates the importance of prevention and monitoring adapted to everyone’s level of risk. For many, self-examinations or observation of the breasts and regular mammograms will be sufficient. For others, who are born with a predisposition, genetic screening adapted to their level of risk and early management may be a better suited option.
About 10% of breast cancers are associated with a hereditary predisposition and this proportion is 20 to 25% for ovarian cancers. Although most of these cancers are not hereditary, individuals with a hereditary predisposition have a much higher risk of developing them at a younger age. For example, a woman who carries a pathogenic variant (associated with the disease) in the BRCA1 gene or the BRCA2 gene, have over 60% chance of developing breast cancer. The risk for ovarian cancer is 40 to 60% for the BRCA1 gene and 10 to 30% for the BRCA2 gene. These same variants also play a role in the development of the pancreas as well as prostate cancer and breast cancers in men.
The presence of certain family history, both maternal and paternal, increases the possibility of hereditary cancer:
- Breast cancer before the age of 45;
- Triple-negative breast cancer before the age of 60;
- A 2nd cancer in the other breast or in the same breast or more than one cancer in the same person;
- Ovarian cancer;
- Breast cancers in men;
- Pancreatic cancer;
- Metastatic prostate cancer or before the age of 55;
- Being of Ashkenazi Jewish descent and diagnosed with one of the cancers mentioned above.
If you recognize yourself in one or more of these antecedents, a meeting with a genetic counselor will allow you to assess your risks and, if relevant, to perform genetic testing to determine if you are a carrier of certain genetic variants associated with a genetic predisposition to cancer.